DISEASES OF THE BONES 395 
the symptom (lameness) of the disease, but an unnerved 
_ horse is not of much good for army purposes. I therefore 
- consider that once the disease becomes firmly established 
it is an unfortunate and incurable one. 
‘Post-mortem reveals the small nodular growths on the 
inner surfaces of the wings of the pedal bone, and if long 
established the ends of the navicular bone are also involved. 
Exudation and gradual growth of false material around 
the nodules takes place, which also serves to increase 
pressure. ’* 
3. ‘This case was brought for my opinion. The horse 
was lame, and walked similar to one that had had lami- 
nitis, putting the heel down first upon the ground. I 
ordered the patient to be destroyed. You will note the 
ossification of the flexor pedis at its attachment to the 
pedal bone. I enclose photos of the ground, also of the 
articular, surfaces of the bone.’+ 
B. PYRAMIDAL DISEASE, BUTTRESS FOOT, OR LOW 
RINGBONE. 
Definition—A condition of periostitis and ostitis in the 
region of the pyramidal process of the os pedis, usually 
preceded, but sometimes followed, by fracture of the pro- 
cess, and characterized by deformity of the hoof and an 
alteration in the normal angle of the joint. 
Causes.—In the majority of cases buttress foot is brought 
about by fracture of the pyramidal process. Thus, although 
distinet evidence of such is nearly always wanting, we may 
assume that the original cause is violent injury to the part 
in question. Properly, therefore, one would say that this 
condition should be described under Fractures of the Os 
Pedis. It appears, however, that other cases of the kind 
arise in which fracture is altogether absent, or in which it 
* Captain L. M. Smith, A.V.D., Veterinary Record, vol. xi., 
p. 229. 
+ F. B. Jones, M.R.C.V.S., Veterinary Record, vol. xi., p. 280. 
